Thuc tieh - Kinh nghiem
Nghien curu cong nghe tai suf dung muol than tir he thong xuf ly l(hi thai nha may nhiet dien
doi dau lam nhien lieu san xuat gach ong
O NGUViN THANH LUAN, THAI TltN D O N G Vidn Ky thudt Nhidt ddi vd Bao ve Mdi trudng (VITTEP)
L
upng mu^i than sinh ra tUhoat d^ng cua cdc nhd mdy nhi^i dien ddt dau rat Idn, len ddn 550 tdn/ndm vdi 1 tdmdy cdng suat 330MW cua Nhd mdy nhi^ di^ 6 Mdn I. Do mudi than chda kim ioai ndng vd pH thap, gdy trd ng^i cho hdu hdt cdc phuong phap xdiy chSt thai nguy hai. Nghien cdu ndy de xudt hudng tdn di^ng mupi than lam nhidn li^ san xudt gach dng d& vdi Id gach lien tuc ki4u ddng. Ket qua thpc nghiem da xdc dinh dupc ty le phdi trpn giOa dat set vd mudi than la 100:8. Vdi ty 1$ ndy, lupng nhiet sinh ra du denung "chin"gach vd dp ben eo ly cung dp hdt nudc cua gach thdnh pham dat TCVN 1450:1998. Han thd nOa, gach thdnh phdm ed do rd rikim loai thap nen an todn v& mdi trudng. Ket qua nghien cuU cho thdy, hudng tan dung mudi than tUnhd may nhiet dien ddt dau dat hieu qua cao, chi phi xuly thap, thdn thifn vdi mdi trudng vd cd the trien khai thuc hien rdng rai.
I . G I d l THIEU
Hdat ddng eae nha may nhiet dien dot dau, ngoai khi thai, ehat thai ran tU he thdng xd ly bui (mupi than) cQng la mdt van de can quan tam vi khdi lupng kha Idn, lai ehda thanh phan nguy hai la kim loai npng va cd pH tha'p, Muoi than neu khong dupc xd ly thich hpp se gay 0 nhiem mdi trudng, anh hudng den sdc khde con ngudi, Hien tai, mupi than td eac nha may nhiet dien ddt dau van duoe xd ly bang phuong phap thieu ddt. tdn kem ehi phi. Trong khi dd, de hudng den mpt tUdng lat phat then ben viJng va than thien vdi moi trudng, eac loai chat thai trudc het nen dupe nghien cdu tai sd dung, tan dung...
nham sd dung eo hieu qua, giam thieu ehi phi xd ly.
Mudi than ehda ham luong 'Carbon kha eao tU 73 den 9 1 % va ehda ham luang cao kim loai Niken, Vanadi [3). Do dd, eac nghien cdu dupe thUc hien chu yeu theo hai hudng chinh nhu sau
Hudng thd nha't la, trich ly kim loai nang trong mudi than de sd dung lai. Trong mudi than eo ehda Vanadi, Molipden va Niken nen viec ngam chiet duac tidn hanh hai giai doan: Giai doan mpt la, dung kiem de chiet Vanadi, Molipden, giai doan hai la. dung H2SO4 de thu hdi Niken; mpt phUdng phap khac la, dung dung dieh (NH4)2S04 de chiet Niken sau dd dung dich kiem de chiet taeh Vanadi.
Hudng thd hai la, tai s d dung mudi than de lam than hoat tinh vdi cae tac nhdn kich hoat hoat tinh khac nhau nhu: Dung hdn hpp axit H2SO4 va HNO3 de tSng didn tich be mat cOa mupi than de viee ap dung mupi than trong dng dung Ipc va taeh; cung cd the diJng aat HCI va axit HF x d ly mupi than trudc khi dung CO2 5 goO^C va eudi cung la dung O j (1%) trong N2 d nhidt do
• 800AC de kich hoat hoat tinh
Ngoai ra, ngudi ta con s d dung muoi than ket vfli eae nguyen lieu khae de san xucit hpp kim.
Trong quy trinh san xua't gach va cac loai IP gach thi gach dupc san xuat t d IP gach lien tuc kieu ddng la ptiu hop vdi viee sd dung muoi than lam nhien lieu do ed hat va nhiet tn so vdi xi than nghien TU thUc te tren, nghien cdu de xuat cdng nghe de x d ly hieu qua mupi than theo hudng tan dung lam nhidn lieu de san xua't gach dng.
2. VAT LIEU V A P H l / O N G PHAP NGHIEN CLfU 2.1. Ddi tUdng n g h i e n cLiru
Chat thai ran (ehi!i yeu la mupi than) phat sinh tif he thdng xd ly khi thai cua nha may nhiet dien ddt dau 6 Mdn I.
2.2. P h u o n g p h a p n g h i e n c i h j
De tien hanh nghien cdu thue nghiem nghidn CLIU, nhdm tae gia tien hanh eae thi nghiem.
5 2 Tdi n g u y e n y g M o i t r a o n g | Ky 2-Thang 11/2012
TN1: Nghien cdu eudng dp nen cOa mau gach kich thudc 5x5x5cm vdi cac ty le phd'i trpn mupi than va dat set khac nhau.
TN2: Nghien cdu tich chat cd ly cCia mSu gach kich thudc 8x8x18cm vdi cac t f le dupe dua ra t d T N L
TN3: Nghien cdu cac van de moi trudng lien quan den gach dng dCing mupi than.
Quy trinh thue hien thi nghiem- Cac nguySn nhien lieu dupe phdi trpn theo t j le,' doi vdi gach kich thUde 5x5x5em viec tao hinh dupc thue hien bang tay, gach kich thudc 8x8x18cm dupc tidn hinh trdn md hinh san xuat thuc te tai IP gach, gach sau khi tao hinh dUpc nung; gach sau khi nung dupc danh gia tinh nang co ly cDa vat lieu theo phuong phap TCVN 6355.1998 va so sanh vdi tiPu ehudn 1450:1998.
3. KET QUA
3.1. Thanh phan mupi than
Thanh phan mudi than duoc trinh bay trong cae bang sau
Bang 1. Ndng dd kim ioai nang trong mudi than theo phuang phap ngam chiet
Bdng 3. Thanh phan hda iy cCia mudi than va xithan
Chi tieu As Ba Cd Co Cr Cu Ni Pb Zn Hq V Mo Se Be Ta Sb Aq
Ddn
mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l mg/l
Phirdng phap phan tich USEPA1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311 US EPA 1311
Muoi than
<0,001 0,042 0,014 1,08 0,135 3,95 104,7
<0,001 7,73
<0,01 171,6 2,48 0,07
<0,001
<0,001
<0.001
<0,001 QCVN 07:2009/BNMT 2 100 0,5 80 5 70 15 250 0,2 25 350 1 0,1 7 1 5
Bang 2 Thanh phan hda hoc cOa mudi than
Chi tieu C 0 S N H
PhtTdng phap phan tich ASTM D 5373 - 02 ASTM D 5373 - 02 TCVN 175 • 1995 AOAC 2010 (993.13) ASTM D 5373 - 02
Ti le muoi than {% khoi luong) 66,4 5,2 3,1 4,8 3,5
Chi tieu Nhiet tri pH Do am D6 tro kho
Ddn vj kcal/kq
%
%
Phi/dng phap phan tich TCVN 200:2007 TCVN 5979 • 1995 Phl/ong phap say TCVN 173:2007
I\flu9i than 4420 3,08
•0,01 38,23
•0,46 12,90
•0,84 Xi than 1470
0,83
•0,02 89,10
•0,10 Nguon: [1]
Bang 4. Thanh phan cac mudi tap chat trong mudi than
Chi tieu NOj- NO,- NH,*
so/-
Ddn vi
mg/g mg/g mg/g mg/g
Phirong phap phan t i c h
S M 4 5 0 0 - N O j ( B ) S M 4 5 0 0 - N O 3 ( E ) TCVN 6179 1996 TCVN 6200:1996
IMuoi than
1,1816 0,081 49,522 168,640
Nguon: [1]
Ngudn: [1]
3.2. Cudng dp nen cua mau gach kich thudc 5x5x5cm
Ty le phdi trpn nguyen lieu dupc dua ra dua tren co sd: Nhiet tri cua mupi than va xi than (nhien lieu hien dang dupe sd dung tai 10 gach); ty le thuc te tai cae 10 nung gach dang sd dung.
Khi thay dd'i ty le phdi trpn nguyen lieu va loai nguyen lieu phdi trpn, thi cUPng dp nen cCia gach la thong sd chiu anh hudng chinh. Do khdng ed tieu chuan so sanh nen viec phan tich eudng dp nen gach mSu kich thuPe 5x5x5em ehi cP tinh ehat tham khao.
cho ta hinh dung sd bd sU bien ddi cudng dp nen eua gach m i u khi thay doi ty le phoi tron cae nguyen lieu.
Cudng dd nen eua gach m i u eh|u su anh hudng eua loai da't set sd dung (mliu I va VI; mau IV va VII), cudng dp nen cua gach mSu giam dan khi tang ty le muoi than tron vdi dat set (mau V, VI, VII, VIM).
6 ty le trpn mupi than vdi da't set td 6 - 8% ( m i u VI va mau VII) thi cudng dp nen eua gach mau khong thay ddi nhieu so vdi ty le 4 % va 10% mupi than ( m i u V va m i u Vlll).
X I than do ham luong tro cao va khdi lupng rieng eao nen khi phdi trpn vdi da't set lam tang cUPng dp nen cua gach m i u ( m i u III) so vdi m i u dat set ddi chdng ( m i u II).
M i u IX va mau X eo euPng dp nen bang nhau cho thay, khi trpn mupi than vdi than da eo sU bien ddi ve cUdng 66 nen khong dang ke.
Tai n g u y e n v o Moi t r a o n g | Ky 2 - Thang 11/2012 K J
3.3. Tinh chat c d ly cua m i u gach kfch thirdc 8x8x18cm
T9 IS phoi trpn di/a vSo: KSt qua phan tfch gach mau l<fch thttdc 5x5x5cm, t } li thi;c t4 tai cSc 16 nung gach dang sCrdung,
Bang 5. Ty /# phdi tr^n dit sit vdi c6c lofi nguydn nhidn lidu lim g$ch miu ttich thudc 8x8x18cm
Ky hieu K M X XM
Thanh phan nguyen
lieu
DS set BD Dat set BD Muoi than oat set BD:
Xi than Da't set BD.
MUOI than
X! than
Tyle
(%)
100 100:8 100:8 1004:4
Bat s6t
(8) 1480 1480 1480 1480
Mu ol tha n (9)
0
1200 60
Xi than
(g) 0 0
120
60So vdi vdi TCVN 1450:1998 thi, tat ca eac thong sd khao sat cLia cae loai gach deu dat yeu cau
Trong qua trinh nung gach trong Id, LTKO gach tron mupi than va gach trpn mupi than va xithan dupe
"thd Ida" danh gia tdt ve mat nhiet luong cung ca'p,
"Ida" on djnh, chay tdt, khong chay "bde", me gach dung muPi than gach "chin" deu, mau sac khPng khac biet so vdi cac me khac; cudng dd uon la thong sd it bi bien ddi nha't, day la dSc thu cOa vat lieu gdm xay dung - CO cudng do udn tha'p. Do trong mudi than ehda nhieu mudi nen dp hut nudc ciJa gach trdn mupi than (mau ky hieu M) co dd hut nUdc eao nhat so vPi cac mau khae, khi trpn mudi than vdi xi than thi cUdng dd nen cua mau cd sU thay ddi kha IPn. lam giam cuong dp nen eCia m i u so vdi m i u gach da't set ddi chdng, tuy nhien dd hut nUPc cua gach lai dUOc cai thien
3.4. Cae van de m o i t r u d n g lien quan den gach dng dung mupi than
Kdt qua phan tich do ro ri kim loai nang trong cac loai gach cho thay, gach san xuat ra cd ndng 60 kim loai nang thap hdn quy chuan QCVN 07.2009/BTNMT quy dinh nen khong la cha't thai nguy hai, so sanh gida 3 m i u gach ta eo the tha'y duoe do rp ri kim loai nang gida gach tron mupi than va gach khPng tron mupi than gan nhU tUdng dUdng nhau Dieu do cho tha'y, viec xi!f ly mupi than theo hudng tan dung lam nhien lieu co hieu qua tdt
Dua vao do ro ri kim loai nSng ra moi trudng eua m i u gach dng ehda mupi than cd the ket luan hUdng
5 4 Tai n g u y e n v o M o i t r a o n g | Ky 2-Thang 11/2012
nghidn cdu tan dung mupi than lam nhidn lieu san xu^t gaeh dng la hoan toan kha thi, an toan vdi mdi trudng khi sd dung va cd thd dng dung tdt trong thuc te de xft ly mupi than.
4. KET LUAN
VPi khdi lupng phat smh khoang 550 ta'n/nam vdi 1 td may c6ng su^t 330MW hoat dpng khdng lidn tue nhi;
hidn nay thl khdi lupng mudi than phat sinh kha Idn, Ndu khdng ed bien phap x d ly triet de vd hieu qua thi kha nang gdy d nhiem mdi trUdng do thanh phan kim loai nang Niken vd Vanadi trong mupi than rat Idn. Tir nghidn edu thUe nghidm trdn, md hinh thuc te da dua ra dupc ty Id phdi trpn thich hpp giua dat set va mudi than la 100:8 n h I m bao dam eac tinh ch^t cd ly cua gach thanh ph^m va bao dam cung c^p du nhiet lupng cho qua trinh nung gach tren md hinh Id gach lien tuc kieu dLftig. Gach san x u l t ra ed tinh an toan cao, dd ro ri kim loai nang th^p va gan xap xf bang vdi gach binh thudng.
TAI UtV THAM KHAO
[1] Nguydn Thanh Luan (2012), Nghien eUu cdng nghe xCt ly mudi than tU he thong xCrly khi thai nha may nhiet dien dot dau theo hudng tan dung lam nhien lieu san xuat gach dng, Luan van thac sT Cdng nghe moi trudng, Vien Moi trudng Tai nguyen - OHQG TP.HCM [2] Hsieh Y. - M . Tsai M. - S , Physical and chemi- cal analyses of unbumed carbon from oil-?red ^y ash.
Carbon 41 (2003) 2317-2324.
[3] Hw^ang S.K.. Pari< J.H, Hong S.U, Jung J H, Jung M Y, Son Y.U and Cho K.J, Engineering Development and Operation for Heavy OH Fly Ash Incineration Plant. KEPRI-93C-T04. Korea Electric Power Research Institute (January 1996)
[4] Stas J, Dahdouh A, Al-ehayah O, Recoveryol vanadium, nickel and molybdenum from ?y ash oi heavy oil-?red electrical pov\/erstation, Chemical Engineering 51/2 (2007) 6 7 - 7 0 .
[5] Tsai S. - L , Tsai M - S , A study of the extractioi\
of vanadium and nikei in oil - fired fly ash. Resource, Conservation and Recycling 22 (1998) 163 - 176.
[6] Xiao Y, Jalkanen H, Yang Y, Mambote C. R, Boom R, Ferrovanadium Production from Heavy Fud Oil Fly Ash and BOF Dust, . , November 2010, Pages 1155-1157
[7] Vietnam/ O Mon project. Course - E8: Item- Boiier and Auxiliaries: Electrostatic Precipitator.
(2007)."
